In all, 56 compounds were detected in samples collected approximately monthly during 2003-05 at the intake for the Clackamas River Water plant. On the basis of this screening-level assessment, adverse effects to human health are assumed to be negligible.

We identified six compounds at concentrations less than human-health benchmarks, but within a factor of 10 of those limits. Those compounds might warrant further study to understand their transport and fate within the watershed.

The 258 organic compounds in this assessment are man-made: pesticides, solvents, gasoline hydrocarbons, personal-care and domestic-use products, pavement and combustion-derived compounds. None were found in concentrations deemed dangerous at this time.

In 2005, about 15.8 million gallons per day (Mgal/d) of water were withdrawn, including 4.12 Mgal/d from groundwater and about 11.7 Mgal/d from surface-water sources.Public supply use accounted for about 78 percent (12.4 Mgal/d) of the total water withdra

In 2005, about 9.52 million gallons per day (Mgal/d) of water were withdrawn, including about 9.33 Mgal/d from groundwater and 0.19 Mgal/d from surface-water. Public supply use accounted for 70% of the total.

This web site is an outgrowth of an agreement between the USGS and the New England Aquarium, designed to summarize and make available results of scientific research. It will also present educational material of interest to wide audiences.

Boston Harbor/Massachusetts Bay Studies research project conducted as part of Boston Harbor cleanup to predict the fate of contaminants and sediments introduced to Massachusetts' coastal waters from sources that include Boston sewage outfall.